Furniture units that are convertible into beds are popular with consumers because of their multifunctionality. Many consumers find it very convenient to have a sofa or chair that can provide a bed for a guest, as such a unit can eliminate the need for an additional, separate bed. One popular sofa-bed design includes its own complete mattress that is folded within the cavity of the sofa during periods of non-use. One such example is illustrated in U.S. Pat. No. 4,200,941 to Gill et al. This type of sofa-bed can be quite heavy, and typically requires not only the separate mattress, but also a relatively intricate mechanism to control the unfolding and folding of the mattress.
Other furniture units lack a complete mattress, but instead are constructed of separate sections that serve as support surfaces of the sofa and unfold to form a flat, mattress-like sleeping surface. One example is shown in U.S. Pat. No. 2,740,131 to Vogel et al.; others are shown in U.S. Pat. No. 5,195,194 to Bradley, U.S. Patent Publication No. 2007/0283491 to Murphy, and U.S. Patent Publication No. 2011/0010847 to Murphy, the disclosure of each of which is hereby incorporated herein in its entirety. The bed shown in the latter of the Murphy publications includes three separate sections that serve as the mattress of the bed: a seat section; an intermediate section; and a head section. A folding mechanism controls the movement of the head, intermediate and seat sections between a folded position, in which the head, intermediate and seat sections are positioned in vertically stacked relationship, with the head section below the intermediate section and the seat section above the intermediate section, the head and intermediate sections being positioned in the cavity of the housing and the seat section serving as the “seat” for the sofa, and an unfolded position, in which the head, intermediate and seat sections are horizontally disposed and serially aligned to form a sleeping surface.
In spite of the existence of these different foldable beds, it may be desirable to offer additional furniture units that can house foldable beds.